Focus on Cellulose ethers

Zvinhu zveCationic Cellulose Ether Solution

Zvinhu zveCationic Cellulose Ether Solution

Iyo dilute mhinduro zvivakwa zveyakakwira-charge-density cationic cellulose ether (KG-30M) pamhando dzakasiyana pH dzakadzidzwa nelaser yekuparadzira chiridzwa, kubva kuhydrodynamic radius (Rh) pamakona akasiyana, uye mudzi unoreva sikweya radius yekutenderera. Rg Chiyero kuRh chinoti chimiro chayo hachina kurongeka asi chiri padyo nedenderedzwa.Zvino, nerubatsiro rwe rheometer, matatu akaiswa mhinduro dze cationic cellulose ethers ane akasiyana machaji densities akadzidzwa zvakadzama, uye pesvedzero yekuisa pfungwa, pH kukosha uye yayo yekuchaja density pane yayo rheological properties yakakurukurwa.Sezvo fungidziro yakawedzera, mutsigiri waNewton akatanga adzikira ndokuzodzikira.Fluctuation kana kunyange kudzokororwa kunoitika, uye thixotropic maitiro anoitika pa3% (chikamu chezhinji).Iyo ine mwero kuchaja density inobatsira kuwana yakakwira zero-shear viscosity, uye pH haina mhedzisiro pane viscosity yayo.

Mazwi akakosha:cationic cellulose ether;morphology;zero shear viscosity;rheology

 

Cellulose derivatives uye yavo yakagadziridzwa inoshanda mapolymers ave achishandiswa zvakanyanya muminda ye physiological uye hutsanana zvigadzirwa, petrochemicals, mushonga, chikafu, zvigadzirwa zvekuchengeta zvega, kurongedza, etc. Mvura-soluble cationic cellulose ether (CCE) imhaka yayo Iine kusimba kwakasimba. kugona, inoshandiswa zvakanyanya mumakemikari ezuva nezuva, kunyanya shampoos, uye inogona kuvandudza kuwirirana kwebvudzi mushure mekugeza.Panguva imwecheteyo, nekuda kwekuenderana kwayo kwakanaka, inogona kushandiswa mune maviri-mu-imwe uye yese-mu-imwe shampoos.Iyo ine zvakare yakanaka application tarisiro uye yakakwezva kutarisa kwenyika dzakasiyana.Zvave zvichishumwa mumabhuku kuti cellulose derivative solutions inoratidza maitiro akaita seNewtonian fluid, pseudoplastic fluid, thixotropic fluid uye viscoelastic fluid nekuwedzera kwekunzwa, asi morphology, rheology uye zvinokurudzira zvinhu zve cationic cellulose ether mune aqueous solution Pane zvishoma. mishumo yetsvakiridzo.Iri bepa rinotarisa pane rheological maitiro equaternary ammonium modified cellulose aqueous solution, kuitira kuti ipe referensi yekushandisa inoshanda.

 

1. Chikamu chekuedza

1.1 Raw zvinhu

Cationic cellulose ether (KG-30M, JR-30M, LR-30M);Canada Dow Chemical Company chigadzirwa, chakapihwa neProcter & Gamble Company Kobe R&D Center muJapan, yakayerwa neVario EL elemental analyzer (German Elemental Company), sample The nitrogen content is 2.7%, 1.8%, 1.0% zvakateerana (the charge density is 1.9 Meq/g, 1.25 Meq/g, 0.7 Meq/g zvichiteerana), uye inoedzwa neGerman ALV-5000E laser light Scattering instrument (LLS) yakayera huremu hwayo pakati pehuremu hwemamorekuru hunosvika 1.64.×106g/mol.

1.2 Kugadzirira kugadzirisa

Muenzaniso wakacheneswa nekusefa, dialysis uye kuomesa-kuomesa.Weresa akatevedzana matatu ehuwandu samples zvichiteerana, uye wedzera yakajairwa buffer mhinduro ine pH 4.00, 6.86, 9.18 kugadzirira iyo inodiwa kusungwa.Kuti ive nechokwadi chekuti samples dzakanyungudika zvakazara, mhinduro dzese dzakaiswa pamagnetic stirrer kwemaawa makumi mana nemasere isati yaedzwa.

1.3 Chiyero chekuparadzira chiedza

Shandisa LLS kuyera huremu-avhareji yemamorekuru huremu hwesample mukunatsa mvura ine mvura, iyo hydrodynamic radius uye mudzi unoreva sikweya radius yekutenderera kana yechipiri Villi coefficient nemakona akasiyana,), uye kufungidzira kuti iyi cationic cellulose ether iri mukati. iyo aqueous solution nereshiyo yayo.

1.4 Viscosity kuyerwa uye rheological kuongorora

Iyo yakaomeswa CCE mhinduro yakadzidzwa naBrookfield RVDV-III+ rheometer, uye pesvedzero yekuisa pfungwa, kubhadharisa density uye pH kukosha pane rheological zvivakwa senge sampuli viscosity yakaongororwa.Pakukwirira kwakanyanya, zvinodikanwa kuti uongorore thixotropy yayo.

 

2. Migumisiro uye nhaurirano

2.1 Tsvagiridzo yeKuparadzira Chiedza

Nekuda kwechimiro chayo chakakosha mamorekuru, zvakaoma kuvapo muchimiro chemorekuru rimwe kunyangwe mune yakanaka solvent, asi muchimiro chemamwe akagadzikana micelles, masumbu kana masangano.

Apo iyo dilute aqueous solution (~ o.1%) yeCCE yakaonekwa neine polarizing microscope, pasi pemashure emuchinjiko mutema orthogonal field, "nyeredzi" makwapa akajeka uye mazariro akajeka akaonekwa.Iyo zvakare inoratidzirwa nekupararira kwechiedza, iyo dynamic hydrodynamic radius pane akasiyana pH nemakona, mudzi unoreva square radius yekutenderera uye yechipiri Villi coefficient yakawanikwa kubva kuBerry diagram yakanyorwa muTab.1. Girafu yekugovera ye hydrodynamic radius basa yakawanikwa pamusangano we 10-5 inonyanya kukwira imwe chete, asi kugoverwa kwakakura kwazvo (Fig. 1), zvichiratidza kuti kune masangano e-molecular-level uye makuru makuru muhurongwa. ;Pane shanduko, uye iyo Rg/Rb tsika dzakatenderedza 0.775, zvichiratidza kuti chimiro cheCCE mumhinduro chiri padyo nedenderedzwa, asi kwete nguva dzose zvakakwana.Mhedzisiro yepH paRb uye Rg haisi pachena.Iyo counterion mune buffer mhinduro inopindirana neCCE kudzivirira iyo charge pacheni yayo yepadivi uye kuita kuti iderere, asi mutsauko unosiyana nerudzi rwekupikisa.Chiyeredzo chekuparadzira kuyerwa kwemapolymer anobhadhariswa anotapukirwa nekubatana kwesimba refu-refu uye kupindira kwekunze, saka pane zvimwe zvikanganiso uye zvipimo muhunhu hweLLS.Kana chikamu chehuremu chiri chikuru kupfuura 0.02%, kune akawanda asingaparadzanise peaks maviri kana kunyange akawanda mapeaks muRh yekugovera dhayagiramu.Sezvo kusungirirwa kunowedzera, Rh inowedzerawo, zvichiratidza kuti mamwe macromolecules anobatanidzwa kana kunyange akaunganidzwa.Apo Cao et al.akashandisa kupararira kwechiedza kudzidza copolymer yecarboxymethyl cellulose uye pamusoro-inoshanda macromers, pakanga paine zvakare isinga patsanuke yakapetwa kaviri, imwe yacho yaive pakati pe30nm ne100nm, inomiririra kuumbwa kwemamicelles pachikamu chemolecular, uye imwe Iyo peak Rh inoenderana. hombe, iyo inoonekwa seyakaunganidzwa, inofanana nemhedzisiro inotarwa mubepa rino.

2.2 Tsvagiridzo yemaitiro erheological

2.2.1 Mhedzisiro yekuisa pfungwa:Pima iyo inooneka viscosity yeKG-30M mhinduro neyakasiyana kutariswa pamhando dzakasiyana dzekugera, uye zvinoenderana neiyo logarithmic fomu yesimba remutemo equation yakatsanangurwa naOstwald-Dewaele, kana chikamu chehukuru chisingapfuure 0.7%, uye mutsara wemitsara yakatwasuka. ine mutsara wekubatanidza coefficients yakakura kupfuura 0.99 yakawanikwa.Uye sezvo kuwedzera kunowedzera, kukosha kweNewton's exponent n inoderera (zvose zvisingasviki 1), zvichiratidza pachena pseudoplastic fluid.Inotungamirirwa neshear force, macromolecular cheni dzinotanga kutsemuka uye kutenderera, saka viscosity inodzikira.Kana chikamu chemazana chiri chikuru kudarika 0.7%, mutsara wekubatanidza koyefisi yemutsara wakarurama wakawanikwa inoderera (inenge 0.98), uye n inotanga kushanduka kana kusimuka nekuwedzera kwekufungisisa;apo chikamu chemazana chinosvika 3% (Fig. 2), tafura Iyo inooneka viscosity inotanga kuwedzera uye inoderera nekuwedzera kweshear rate.Iyi nhevedzano yezviitiko zvakasiyana nemishumo yeimwe anionic uye cationic polymer mhinduro.Iko n value inokwira, kureva kuti, iyo isiri yeNewtonian pfuma haina simba;Newtonian fluid is viscous liquid, uye intermolecular slippage inoitika pasi pechiito cheshear stress, uye haigoni kudzorerwa;isiri-Newtonian fluid ine inodzoreredzwa elastic chikamu uye isingadzokeke viscous chikamu.Pasi pechiito chekuveura kushushikana, kutsvedza kusingadzoreki pakati pemamorekuru kunoitika, uye panguva imwe chete, nekuti macromolecules akatambanudzwa uye akatariswa neshear, inodzoreredzwa elastic chikamu chinoumbwa.Kana simba rekunze rabviswa, macromolecules anowanzo dzokera kune yekutanga yakakomberedzwa fomu, saka kukosha kwe n kunokwira.Iko kusungirirwa kunoramba kuchiwedzera kuumba network network.Kana shear stress idiki, haizoparadzwi, uye chete elastic deformation ichaitika.Panguva ino, elasticity ichave yakawedzerwa, iyo viscosity ichave isina simba, uye kukosha kwe n kuchaderera;nepo shear stress iri kuwedzera zvishoma nezvishoma panguva yekuyera maitiro, saka n Kukosha kunoshanduka.Kana chikamu chemazana chinosvika 3%, iyo inooneka viscosity inotanga kuwedzera uye yozoderera, nokuti shear duku inokurudzira kudhumhana kwema macromolecules kuti iite mahombekiti makuru, saka viscosity inokwira, uye shear stress inoramba ichiputsa zvikamu., iyo viscosity ichaderera zvakare.

Mukuferefetwa kwethixotropy, isa kumhanya (r/min) kuti usvike painoda y, wedzera kukurumidza panguva dzenguva dzose kusvika yasvika pamutengo wakatemerwa, uye wobva wadonha kubva pahupamhi hwekumhanya kudzokera kune yekutanga kukosha kuti uwane inoenderana. The shear stress, hukama hwayo neshear rate inoratidzwa muFig. 3. Kana chikamu chemazana chiri pasi pe2.5%, mutsara wepamusoro uye wakadzika pasi unopindirana zvachose, asi kana chikamu chemazana chiri 3%, mitsetse miviri kwete. Kureba kwakapetwa kaviri, uye mutsetse wokudzika unosara shure, zvichiratidza thixotropy.

Iyo nguva yekutsamira kweshear stress inozivikanwa se rheological resistance.Rheological resistance hunhu hune hunhu hwe viscoelastic zvinwiwa uye zvinwiwa zvine thixotropic zvimiro.Inowanikwa kuti y yakakura iri pachikamu chemazana, iyo inokurumidza r inosvika pakuenzanisa, uye nguva yekutsamira idiki;pachikamu chakaderera chemazana (<2%), CCE hairatidzi rheological kuramba.Apo chikamu chemazana chinowedzera kusvika ku2,5%, chinoratidza nguva yakasimba yekutsamira (Fig. 4), uye zvinotora anenge maminitsi gumi kusvika pakuenzana, nepo pa3.0%, nguva yekuenzanisa inotora maminitsi makumi mashanu.Iyo yakanaka thixotropy yehurongwa inokodzera kune inoshanda application.

2.2.2 Mhedzisiro yechaji density:iyo logarithmic fomu yeSpencer-Dillon empirical formula inosarudzwa, umo zero-cut viscosity, b inogara iri pahutano hwakafanana uye kupisa kwakasiyana, uye inowedzera nekuwedzera kwehuwandu pane imwe tembiricha.Zvinoenderana nemutemo wesimba equation yakatorwa naOnogi muna 1966, M ndiyo inoenderana molecular mass yepolymer, A uye B iconstants, uye c ndicho chikamu chehuwandu (%).Fig.5 Iwo matatu macurve ane zviripachena mapoinzi ekutenderera akatenderedza 0.6%, kureva kuti, pane yakakosha misa chidimbu.Kupfuura 0.6%, zero-shear viscosity inowedzera nokukurumidza nekuwedzera kwehutano C. Mapeji ematatu matatu ane masheji akasiyana-siyana ari pedyo zvikuru.Kusiyana neizvi, kana chikamu chehuwandu chiri pakati pe0.2% ne0.8%, zero-cut viscosity yeLR sampuli ine diki yekuchaji density ndiyo yakakura, nekuti hydrogen bond association inoda imwe yekubata.Naizvozvo, density yekuchaja yakabatana zvakanyanya nekuti macromolecules anogona kurongeka nenzira yakarongeka uye yakabatana;kuburikidza neDSC kuyedzwa, inowanikwa kuti LR ine isina kusimba crystallization peak, ichiratidza yakakodzera kuchaja density, uye zero-shear viscosity yakakwira panguva imwecheteyo.Kana chikamu chikuru chiri pasi pe 0.2%, LR ndiyo idiki, nekuti mumhinduro yakaderedzwa, macromolecules ane low charge density anowanzo kuumba coil orientation, saka zero-shear viscosity yakaderera.Izvi zvine zvakanaka kutungamira kukosha maererano nekukora kuita.

2.2.3 pH maitiro: Mufananidzo 6 ndiwo mugumisiro wakayerwa papH yakasiyana mukati mehuwandu hwe 0.05% kusvika 2.5% chikamu chehuwandu.Pane inflection point yakatenderedza 0.45%, asi matatu macurves anenge adhumhana, zvichiratidza kuti pH haina mhedzisiro iri pachena pazero-shear viscosity, iyo yakasiyana zvakanyanya nekunzwa kweanionic cellulose ether kusvika pH.

 

3. Mhedziso

Iyo KG-30M dilute aqueous solution inodzidzwa neLLS, uye iyo hydrodynamic radius kugovera yakawanikwa ndeye yepamusoro imwe chete.Kubva pakona kutsamira uye Rg/Rb reshiyo, inogona kutaurwa kuti chimiro chayo chiri padyo nedenderedzwa, asi isiri yenguva dzose zvakakwana.Kune zvigadziriso zveCCE zvine hutatu hwekuchaja densities, viscosity inowedzera nekuwedzera kwehuwandu, asi nhamba yekuvhima yaNewton n inotanga kuderera, zvino inoshanduka uye kunyange kusimuka;pH haina mhedzisiro pane viscosity, uye ine mwero kuchaja density inogona kuwana yakakwira viscosity.


Nguva yekutumira: Jan-28-2023
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